Keeping on grade while grading with a back hoe and screed continues to be a challenge even for the most experienced operators. More so than most digging machines, the extended lever arm of the hoe combined with the downward digging forces applied produce unwanted wiggling and vibration of the hoe arm and screed blade. Even experienced operators, having developed a tactile ‘feel’ for how well the screed is digging and cutting, have difficulty maintaining grade, and the more precisely the grade must be maintained, the more difficult and draining the job. While very good operators are able to maintain grade reasonably well even over prolonged digging sessions, the effort does take its toll both physically and mentally.
Conventional laser alignment and even GPS-guided devices have been developed to give the operator more reliable feedback regarding how close the grading screed is to the desired grade. Such devices provide feedback to the operator that the blade is too high, too low, or on grade at any given time during the digging operation. However, the operator must still receive and manually respond to the feedback signals (i.e., up or down) provided by the devices. Such constant correction of the bucket depth has proven to be physically demanding and exhausting.
Thus, there is a need for a system for automatically assisting grading and for automatically keeping the excavation on a predetermined grade. The present novel technology addresses this need.